Center for Problem-Oriented Policing

The Problem of Missing Persons

What this guide does and does not cover

This guide begins by describing the problem of missing persons and reviewing factors that increase its risks. It then identifies a series of questions to help you analyze your local missing persons problem. Finally, it reviews responses to the problem and what is known about these from evaluative research and police practice.

This revised second edition adds a lengthy chapter on Missing and Murdered Indigenous Persons (MMIP), as well as adding information and guidance specific to MMIP throughout the guide.

Law enforcement’s effort to locate and return missing persons is but one aspect of the larger set of problems related to the reasons people go missing. This guide is limited to addressing the particular issues associated with missing persons. Related problems not directly addressed in this guide, each of which requires separate analysis, include the following:

Abuse in care facilities
Child abuse
Child custody abductions
Child exploitation
Child sexual abuse
Child sexual abuse / exploitation material (sometimes called child pornography)
Domestic violence
Elder abuse
Homelessness
Homicide
Human trafficking
Illegal immigration and border crossing
International abductions
Juvenile runaways
Kidnapping
Life insurance fraud
Natural disasters
Outstanding warrants (e.g., for failure to appear in court)
Persons lost in the wilderness
Sex work
Sex offenders
Unidentified dead
Walkaways from assisted living facilities

Some of these related problems are covered in other guides in this series. For the most up-to-date listing of current and future guides, see www.popcenter.org.

General description of and factors contributing to the problem

For purposes of this guide a missing person is a person 18 years old or older whose disappearance may not be voluntary, or a child whose whereabouts are unknown to the child’s legal custodian and the circumstances of whose absence indicate that 

1. the child did not voluntarily leave the care and control of the custodian, and the taking of the child was not authorized by law; or
2. the child voluntarily left the care and control of the child’s legal custodian without the custodian’s consent and without intent to return.

State agencies work to coordinate reports of missing persons with federal agencies, such as the National Crime Information Center (NCIC). In states with an Amber Alert Plan, parents of a missing or abducted child can contact their local police or sheriff’s department to file a missing persons report. There is no 24-hour waiting period; the law enforcement agency will immediately enter information about the missing child into both its own missing persons database and the National Crime Information Center’s Missing Person File.¹

In the United States, missing persons cases have declined steadily since the 1990s, from a high of nearly one million in 1997 to about 520,000 in 2021.^2,* It is likely, however, that this figure undercounts the actual number of missing persons, especially among groups that are reluctant to report disappearances to the police. Since 1975, the National Crime Information Center (NCIC) system has collected data on nearly 25 million persons reported missing, of whom approximately 100,000—about 0.4 percent—remain missing as of 2022.† The overwhelming majority of missing persons are eventually discovered, either alive or dead.

* In Canada, 70,000 to 100,000 persons per year are reported as missing (Huey and Ferguson 2023). In the United Kingdom, about 300,000 per year are (Fyfe, Stevenson, and Woolnough 2015). Unless otherwise noted, the data presented in this guide are for the United States.

† NCIC, because it is only one of the national sources of missing persons data, should be used cautiously to draw research conclusions, as it does not meet the requirements of a statistical/scientific database; rather, NCIC is an operational database. Data are entered by thousands of different people with varying levels of understanding about missing person categories and definitions. Changes in certain categories over time may reflect greater understanding of appropriate assignment rather than real change in a category. For example, declines in the overall category of “juvenile” in NCIC may reflect a better assignment of cases of missing persons under age 18 to other more appropriate categories of “endangered,” “involuntary,” or “disabled” missing persons.

Missing persons cases can consume a lot of police and other resources, more than is commonly realized.³ Moreover, in high-profile cases police executives can feel a great deal of  pressure to authorize those resources to maximize the chances of locating the person and to be seen as doing all that they can.⁴

Classifying missing persons cases

Police, researchers, and missing persons organizations classify cases in a variety of ways and for a variety of purposes. Common classification schemes are based on the missing person’s demographics (e.g., age, gender, race, ethnicity), risk of harm, and suspected reason for being missing. Because classification can determine the urgency, investigative strategy, and amount of resources police assign to each case, you should carefully consider how your agency classifies cases.

For missing persons cases where circumstances were known (about half of all cases), 95 percent were classified as “juvenile runaway” (see “Missing juveniles” beginning on page 13 for further discussion of juvenile runaway cases).^5,* The remaining known circumstances included approximately 2,500 cases of abductions by noncustodial parents and approximately 500 cases of “abductions by strangers” (involving both juvenile and adult victims).

* Because NCIC cases must be entered by police within two hours of reporting them, it is likely that police eventually know much more about the circumstances of many of these disappearances at a later time.

Women and men are proportionately represented among missing persons. White subjects account for about 57 percent of missing persons, Black subjects for 35 percent, Asians and Native Americans for about 2 percent each, with about 3 percent of missing persons’ race being unknown.⁶ Black and Native American communities are overrepresented, while White and Asian communities are underrepresented as missing persons. However, White people—particularly attractive, young, White women and girls—appear to receive the bulk of media and social media⁷ attention in missing persons cases, with less or no media coverage for missing minorities or those deemed less attractive or less sympathetic.⁸

Some missing people are missing voluntarily and others involuntarily. Each of these categories includes several subtypes of missing persons with potentially different investigative strategies for police. NCIC categorizes the missing as “juvenile,” “endangered,” “disabled,” “other,” “involuntary,” and “catastrophe.” Some of these categories describe characteristics of missing persons, others describe their temporary condition, and others describe their willingness to be missing.* The most likely entry is juvenile (62 percent), followed by other (23 percent), endangered (8 percent), disabled (5 percent), involuntary (2 percent), and catastrophe (less than 1 percent).⁹ However, natural disasters such as hurricanes, earthquakes, fires, and floods can add significant numbers to the catastrophe category in affected jurisdictions.

* The NCIC categorization scheme may not be of significant operational value for police; accordingly, police agencies are encouraged to develop their own categorization schemes that best reflect the nature of their missing persons cases.

Common categories based on the circumstances under which a person goes missing are the following:

• Individuals not fully capable of caring for themselves (e.g., because of mental illness, developmental disability, intoxication)

   

• Individuals voluntarily seeking a better life situation (e.g., runaways, fugitives)

   

• Individuals who do not consider themselves to be missing, but others do (e.g., taking a trip without notifying others)

   

• Individuals abducted by strangers or acquaintances (e.g., human trafficking, kidnapping)

   

• Individuals taken away by family members or other caretakers (e.g., child custody disputes)

   

National, as well as local, counts of missing persons for any given year are constantly changing as cases are listed by the date they occurred (i.e., when the persons went missing or were last seen) and not by the date the cases were entered in the record system. Persons who actually went missing in one year may not be reported as missing until years later. Because of the categorization scheme, the overlap among some categories—and the large gap in knowledge about the circumstances of many missing persons—the scope and nature of the missing persons  problem is unclear. Your jurisdiction might have numbers of certain types of missing persons that differ from the national picture.

Repeat missing persons

A relatively small proportion of missing persons account for a disproportionately high percentage of missing persons reports because they go missing repeatedly. The data for young people is especially skewed by a small number of repeat teenage runaways;¹⁰ by one calculation, the 5 percent of young missing persons who were reported missing 10 times or more accounted for 30 percent of total reported missing young people.¹¹ One Australian study found that 34 percent of missing persons had gone missing previously.¹² As many as 4 percent of missing children experienced multiple missing episodes during the course of a single year, the most likely combination being a runaway episode and an episode of whereabouts unknown to caregivers (but otherwise safe).¹³ Cases of repeat runaways use a huge amount of police resources and may result in less attention being paid to repeated disappearances of the same individual.¹⁴ Repeat runaway cases may indicate family dysfunction, child abuse, sexual exploitation, substance abuse, or some combination of these factors.¹⁵

Harms to and by missing persons

The harms that missing persons experience or that their missing status causes to others vary. At the top of the harm spectrum, some missing persons are raped, otherwise assaulted, or murdered. By one estimate, 10 percent of missing persons cases involve some form of violence, including homicide, nonfatal assault, sexual assault, stalking, coercive control, and psychological aggression, with violence across all these types being somewhat more likely when the missing person is female.¹⁶ At the other end of the spectrum, some missing persons experience little or no harm: They were never in danger but only unaccounted for, or they wished to go missing to escape worse consequences. In the middle of the spectrum, some missing persons are injured or become ill because they did not have support or protection during the time they were missing. Others experience psychological trauma because they have been abducted, held captive, or experienced fear and anxiety from not knowing whether they would be found and rescued.¹⁷

People who care for missing persons—whether family, friends, guardians, caregivers, or coworkers—experience anxiety and stress from not knowing whether the missing person is safe.¹⁸

Finally, all community members experience some difficult-to-quantify but elevated risk to their safety when public safety resources are consumed by searching for missing persons who are not, in fact, in any danger. A single missing persons search can consume hundreds of hours by police, fire and emergency, helicopter, dive team, and canine unit personnel.

Assessing risks for missing persons

There are two main types of risk at issue missing persons cases: (1) the risk that a person will go missing and (2) the risk that the missing person will come to harm. The first type implicates measures that can be taken to prevent people from going missing. The second determines the urgency and amount of resources police and others should devote to finding the missing person.

Assessing risk for going missing

Reliably assessing risk for going missing requires considering multiple factors rather than a single factor. At a minimum, the interaction of the following types of factors should be understood:

• Demographic status (e.g., age, race/ethnicity, gender)

• State of mind (e.g., mental illness, suicidal ideation, or other vulnerability)

• Physical and social environment from which people go missing¹⁹

• Prior instances of going missing.

The following people are experiencing common combinations of factors that put them at relatively high risk of going missing:

• A teenager seeking to escape abuse or conflict at home

• A teenager struggling to reconcile traditional and modern cultural expectations

• A teenager living in a foster or group home

• A married person contemplating divorce but with poor coping skills

• A sex worker working on the street without physical protection

• A person suffering from memory impairment, schizophrenia, suicidal ideation, or other mental illnesses

• A young child living in a new, unfamiliar community

• A homeless person with a substance use disorder

• A person experiencing sudden and severe economic loss

Assessing risk for harm after going missing

A small proportion of people who go missing suffer physical harm while missing, with an even smaller proportion being killed.^20,* However, where there are indications that the missing person had suicidal ideations, the risk that the person will die by suicide while missing is relatively high.²¹ Because police cannot know for certain ahead of time who is at risk of harm, and because they lack the resources to give every missing persons case the fullest attention, some risk assessment to prioritize cases is necessary.† This risk assessment might be as simple as sorting cases into two priorities: one justifying immediate investigation and search, and the other justifying only monitoring the situation until there is reason to believe the missing person will not be located without an investigation and search.^22,‡

* One UK study calculated that only 0.3 percent of missing persons cases had a fatal outcome (see Tarling and Burrows 2004, as cited in Newiss 2004).

† British police agencies commonly employ the THRIVE (Threat, Harm, Risk, Investigation, Vulnerability, Engagement) risk-assessment model (College of Policing 2024).

‡ For a discussion of the ethics of missing persons investigations, see Kim, Leach Scully, and Huston Katsanis (2016).

Across all missing persons cases, an estimated 10 percent suffer some harm while missing.²³ What little reliable research there is suggests that women and girls are at higher risk of being harmed while missing than men and boys, and that young children are at higher risk than older children or adults.²⁴

The research evidence on age and sex risk differences is not yet strong, so you must blend research-based risk assessments, standard operating procedures, experiential understanding of missing persons in that community, and, of course, the particular circumstances of each case to calculate risk.²⁵

Missing persons cases are not conventional criminal investigations, and most do not involve a crime. But because what originally seems a mere routine missing persons case sometimes entails a far more serious matter, prioritizing potentially high-risk cases is essential. Because missing persons cases can consume a significant amount of police resources, agencies can reap significant rewards by preventing them or responding in a more efficient manner.

The missing persons case least likely to be viewed as unusual or suspicious—the case of the missing adult sex worker with a warrant—may in fact be the case at the highest risk for foul play. Or what may appear to be a typical missing child case may in fact have the police responding to a crime in progress—an abduction, a kidnapping, a molestation, a rape, or a murder.* While the missing elderly person or autistic child may not be at significant risk for foul play, they may face significant risks of accidental death, including by exposure or drowning. Assessing risk, while difficult, is a critical component of missing persons investigations, and cases should not be assumed to be of low priority until the initial investigation can be conducted.²⁶

* Cases involving child abduction that may present a danger to the child are eligible for the “Child Abduction” (CA) flag when entered into NCIC as involuntarily missing or endangered missing (NCMEC 2006).

In some missing persons cases, there will be obvious signs of foul play, such as evidence of a struggle or of a home or a car in disarray. But in cases originally suspected to be benign, additional information may suggest the missing person is at high risk. Family abduction cases also have varying levels of risk. Cases where a child is taken out of state, those where there is a family history of abuse or danger of sexual exploitation, and those involving children with special medical needs may present greater than average risk  n family child abduction cases.²⁷ Thus, the risk or urgency in a particular case can change over time as you gather information.

Risk factors for missing children

The following factors may put youth at an increased risk of running away or becoming homeless:²⁸

• Physical or sexual abuse

• Family conflict

• Lack of acceptance of gender identity or sexual orientation

• Struggling to manage mental health

• Substance abuse

• Medical issue or developmental or physical disability

• Pregnancy

• Online enticement

• Separation from a friend, romantic partner, or biological family

• Gang activity

• Sex trafficking

• Social rejection or bullying

Missing juveniles

Broadly, a “missing child refers to any youth under the age of 18 whose whereabouts are unknown to his or her legal guardian.”²⁹ The total annual number of children who go missing each year—both reported and unreported—is estimated to be around 1.3 million.³⁰ Of these missing children, nearly all return home alive or are located; less than one percent are not. Most missing children are found within a few miles of where they went missing.³¹ Of those relatively few children who remain missing, the majority are runaways from institutional care.³² The most common categories of missing children, from most frequent to least frequent, are as follows: juvenile runaways, family abductions, lost or injured children, and nonfamily abductions.³³

Juveniles account for approximately half of active missing persons cases.³⁴ Three-quarters of missing children are ages 12–17. Male and female children have a nearly equal likelihood of going missing. About 55 percent of missing children are White, 20 percent are Black, and 20 percent are Hispanic.³⁵

In child abduction murders, there is a nearly equal likelihood that the perpetrator is a stranger as that the perpetrator is a friend or acquaintance, and the median victim is 11.5 years of age. The mean age of offenders is 27.8. Offenders are typically unmarried and as likely to be unemployed as employed; their initial contact with the victim usually occurs within three blocks of the victim’s residence (and in many cases within a half-block). A 2006 study reported that in only about half of these cases were the victims reported as missing and, in many cases, there was at least a two-hour delay in reporting them to police.³⁶

Most missing children (84 percent) are runaways or are missing for benign reasons. The most common categories of missing children are not necessarily those in which the child is at greatest risk. The least common missing-child case is the most dangerous—stranger abductions. However, initially, police may not know if the reason the child is missing is a brief runaway episode, getting lost, a miscommunication about the child’s whereabouts, or a stranger abduction; this uncertainty is one reason the initial investigation is so important.

National Center for Missing and Exploited Children

Established in 1984, the National Center for Missing and Exploited Children (NCMEC) is a nonprofit, private organization which serves as a clearinghouse for information on missing and exploited children. NCMEC provides technical assistance and training to law enforcement and social service professionals, distributes descriptions and photographs of missing children, and networks with other nonprofits and state clearinghouses for missing children.

National Missing and Unidentified Persons System (NamUs)

In existence since 2008, the National Missing and Unidentified Persons System (NamUs) is sponsored by the National Institute of Justice. NamUs is a national clearinghouse for information and includes an online system for recording missing persons, unidentified dead, and unclaimed dead, accessible through the NamUs website at https://namus.nij. ojp.gov. The NamUs database can be accessed and searched by anyone—police, medical examiners or coroners, and families. Cases and updates to existing cases are vetted by NamUs experts before they are added, and police and coroners can keep sensitive case data away from public display. Only coroners and medical examiners are authorized to enter unidentified and unclaimed dead cases. The databases are linked, and searches can be performed by using a number of different identifiers, including scars, tattoos, clothing, jewelry, and DNA. NamUs cleared 18 previously unresolved cases in its first 18 months.

NamUs improves the efficiency with which dental records and other radiographs can be shared with experts; has extensive search capabilities; allows free access to expert anthropologists, odontologists, and fingerprint examiners; and provides free DNA testing. It allows for automatic searching of two of the databases to find similarities in missing persons and unidentified dead cases. NamUs can help police and missing persons’ families only if police enter their missing persons cases into the system.

Juvenile runaways

Runaway and thrownaway juveniles (children forced from their home or abandoned) constitute the most significant portion of missing persons cases.³⁷ As many as 1.7 million children run away from home each year, with approximately 20 percent of those cases reported to police. Most runaway episodes last only a day or two—75 percent of such juveniles return home within a week—and most do not leave the local area.^38,*

* See Problem-Specific Guide No. 37, Juvenile Runaways, 2nd edition, for further information.

Although most runaway cases do not result in an arrest, there are approximately 100,000 juvenile runaway arrests each year.³⁹ NCIC statistics show a decline in the number of juvenile runaways over the past few years, and this decline may reflect improvements in child well-being, such as reductions in teenage pregnancy and alcohol use as well as general declines in violence and other victimization.⁴⁰ However, runaway cases still require a huge amount of police resources and may involve sexual, physical, and emotional abuse. Juvenile runaways are at an increased likelihood (compared to their peers) of physical, drug, and sexual abuse; suicide; and sexual exploitation.⁴¹ A focus on high-risk victims can not only lead to reductions in repeat runaway behavior but also help address child exploitation and trafficking, sexual assault, and organized crime.⁴²

Children missing from care

Children missing from care can be missing from institutional facilities or from alternative in-home care, such as foster care. Children in care are afforded more confidentiality protections than those not in care; thus, getting necessary information about these missing children may present challenges. Of the nearly 600,000 foster children in the United States, as many as 20 percent are missing from care at any given time, and most of those (98 percent) are considered runaways. The remaining 2 percent are unaccounted for, and their status is unknown.⁴³ Some of these children have been taken by family members, and many have run away, and some proportion of both groups is at risk for homicide, suicide, or accidental deaths.

Abductions of children by strangers (stereotypical child kidnapping)

Although abductions of children by strangers are rare, they are high-profile cases, require a huge amount of police resources, and often pose a significant risk to the child.⁴⁴ An estimated 115 child abductions by strangers occurred during the most recent study year (2022) of the National Incidence Studies of Missing, Abducted, Runaway, and Thrownaway (NISMART) Children.⁴⁵ Only about 100 children per year are victims of stereotypical kidnapping; most are pubescent girls who are assaulted or otherwise physically abused in some fashion. These abductions are equally likely to occur during spring, summer, and fall. The lower number of winter abduction cases likely mirrors other crime patterns that decline during winter months, when there is less opportunity for crime; in these cases, fewer children are outdoors without supervision. Men and older boys are the abductors in 93 percent of abductions by strangers, and persons in their twenties constitute about one-third of the abductors. Of these cases, 40 percent result in the murder of the child, and an additional 32 percent of the abducted children are injured. In abductions in which the child is murdered, the killer is about equally likely to be a stranger as to be known to the child. The killers commonly have prior arrest histories for violence against children, and most are motivated to abduct the child for sexual gratification.⁴⁶

Nonfamily abductions

In addition to stereotypical child abductions or kidnappings by strangers, each year there are approximately 58,000 child victims of nonfamily abductions perpetrated by friends, acquaintances, and strangers in diverse situations. These abductions, although sometimes involving strangers, differ from the stereotypical abductions / kidnappings by strangers in terms of offender intent and other case characteristics.⁴⁷ Police data do not reflect nearly this number, as only about half of nonfamily abductions are reported to police; because such abductions are not commonly perceived to be dangerous situations, caretakers think the child will return, or caretakers do not even know about the episode.⁴⁸ Nonfamily abductions, as opposed to stereotypical kidnappings, typically involve less forced movement and detention (but may involve moving the child using physical force or threat, detaining the child for at least an hour, or luring a child 15 or younger for purposes of concealment or with intent to keep the child permanently). In only about one-fifth of nonfamily abductions are police initially contacted to help locate the abducted child. In a 2002 study, teenagers were the most likely victims in nonfamily abductions (81 percent of nonfamily abduction victims were 12 or older); girls account for 65 percent of victims; and in nearly half of the cases, victims were sexually assaulted.⁴⁹ 

About one-half of nonfamily abductions are perpetrated by someone known to the child, including friends, neighbors, caretakers, or other persons of authority.⁵⁰ Men are the abductors in three-fourths of nonfamily abductions, and persons in their 20s commit nearly half of nonfamily abductions.

The most likely place of a nonfamily abduction is an open area, such as a street, a public place, or wooded area. Sexual assault is the primary motive in nonfamily abductions. Weapons are involved in fewer than half of nonfamily abductions.⁵¹

There are relatively few cases of nonfamily infant abductions—only about 3–14 cases nationwide per year—and even that figure appears to be declining. Historically, they occurred primarily in health care facilities and were committed by women seeking a baby, often following a faked pregnancy.⁵² Most of these infants (more than 90 percent) are successfully recovered, quick reporting to police being vital to recovery.⁵³ However, because of increased healthcare facility security, about half of these still rare cases now occur at the home of the mother or elsewhere. Some of these cases (18 percent) involve violence, and some (about 10 percent) involved the killing of the mother—and, more rarely, the killing of both parents. In many of the cases involving the death of the mother, the infant is abducted by cesarean section at the mother’s or the offender’s home.⁵⁴

Family abductions

Most abductions of children are perpetrated by noncustodial parents, sometimes referred to as “family abductions.”* Based on surveys of youth, about one million children a year are victims of family abductions; slightly fewer than one-half of cases are reported to police. About 60 percent of family abductions are perpetrated by the mother or a female relative and 40 percent by the father or a male relative, although those ratios are reversed when the abduction constitutes a kidnapping.⁵⁵ Female children are a bit more likely to be the victims in family abductions. The most likely place that abductions occur is the child’s or someone else’s home or yard; school or day care abductions are relatively rare. The majority of the children abducted are with the abductor just before the abduction; typically, in these abductions, the children are not returned to the custodial parent after visits. Family abductions are more likely to occur in the summer. Most of the children (91 percent) are returned. Contributing factors to family abductions may include unresolved conflicts over child custody issues that make abduction seem a last option. Children are often psychologically traumatized by these abductions, and family abductions often are associated with various other forms of abuse of the child.⁵⁶

* Laws on criminal custodial interference vary from state to state.

Family abduction cases may be prolonged and may sometimes involve international implications. There have been a number of legislative initiatives affecting family abductions (see appendix B). These cases involve significant legal, civil, and liability issues regarding the enforcement of the most recent custody order.⁵⁷ According to NCMEC officials, about half of international cases of U.S. child abduction involve abductors who flee or are at risk of fleeing to Mexico.⁵⁸

Children missing involuntarily, lost, or injured (MILI) or missing because of benign explanations (MBE)

Missing children who do not fall within any of the above categories are commonly missing because of miscommunication: They are too young to contact a caretaker; or they are lost, stranded, or injured and therefore unable to contact a caretaker. As many as 200,000 children a year are involuntarily missing from caretakers because they were lost, injured, or stranded. These children are most commonly White male teens who disappeared from wooded areas or parks. An additional nearly 350,000 children are missing for benign reasons; they are not actually lost, injured, abducted, victimized, or runaways. Rather, their cases were basically false alarms.⁵⁹ Most of those missing for benign explanations are teenagers who failed to return home when expected. The reasons for these types of cases (MILI and MBE) can include car trouble or car accidents, inclement weather, poor communication, helping a friend, riding the wrong bus, truancy, or sleeping in unknown places. Most of these children are teenagers, missing for fewer than six hours.⁶⁰ Although these categories of missing children account for far greater numbers than kidnapped or abducted children, less attention has been paid to preventing cases of MILI and MBE children than to resolving cases of runaway and abducted children. In areas where hiking, camping, boating, flying, rock climbing, and other outdoor activities are popular, police may encounter more of these cases. Children missing for the reasons described here often come from families that are otherwise socially and economically stressed, a confluence of factors that leave such children more vulnerable to going missing.⁶¹

Missing adults

In the United States, adult missing persons cases are categorized as follows:⁶²

0. Disabled. A person of any age who is missing and who is physically or mentally disabled or senile and thereby subject to personal and immediate danger
1. Adults missing involuntarily. A person of any age who is missing under circumstances indicating that the disappearance was not voluntary
2. Endangered. A person of any age who is missing under circumstances indicating that that person’s physical safety may be in danger
3. Catastrophe. A person of any age who is missing after a catastrophic event

4. Other. A person who is missing, declared unemancipated as defined by the laws of the person’s state of residence, and does not meet any of the entry criteria set forth in items 1–4.

    

Slightly more than half of all active missing persons cases are missing adults, and thus, at any given time, there are about 100,000 active missing adult cases in police files.^63,* While men account for about 60 percent of all (not just active) missing adult cases, younger missing adults are disproportionately women.⁶⁴ About two-thirds of missing adults are White; about one-fourth are Black; and about 5 percent are American Indian, Asian, or other races.⁶⁵ Black people are again disproportionately represented as missing adults, although not quite at the level of missing children.

* In the past, when a missing child turned 18 years of age, some police agencies removed the missing child cases from their records. However, the 2006 Adam Walsh Act mandates that these records be converted to missing adult cases (NCMEC 2006).

Adults missing voluntarily

Unlike juveniles, adults can legally choose to go missing, and often they do so out of a wish to escape relationship difficulties, financial problems, or depression or just to disappear. When police locate these persons, they are not permitted to divulge their location to those who reported them missing—just that they were located and do not wish to be contacted. Although adults have the right to go missing and may in fact not be officially missing, police resources are consumed by following up on these missing adult cases to determine the circumstances.

Persons missing in disasters

Natural disasters and catastrophes can also cause adults and children to go missing. Some will have been injured or killed in the disaster, but their bodies have either not been found or identified.⁶⁷ Some will be alive but will have fled the disaster area and not yet notified people of their whereabouts. Police and other rescuers will be under great pressure to announce who has been found, dead or alive, so accuracy is critical but slow to emerge.

The “missing missing” or murdered

Most missing persons are not reported as missing to police. Some proportions of these missing persons—the “missing missing”—were victims of foul play and in hindsight were clearly involuntarily missing and endangered.

Sex workers

Sex workers are a particularly vulnerable pool of victims of serial murder. In many cases, these victims are not part of police missing persons cases because no one reported them as missing or because they had outstanding warrants and departmental policy was not to accept missing persons cases for those with outstanding warrants.⁶⁸ Presumably, the logic behind this procedural rule was that those with outstanding warrants were considered more likely to be fugitives than missing. In the Green River sex worker serial murder case in Washington and Oregon in the 1980s and 90s, 11 of the 48 victims had no active missing persons case. An additional five victims were unidentified dead and were also likely to have been among the “missing missing,” meaning that as many as one-third of the victims were not known to be missing before their deaths. Many other recent serial murder cases have included “missing missing” victims.^69,* Although some missing persons risk assessments would categorize those with outstanding warrants for nonviolent crimes as low-urgency cases,⁷⁰ these cases can in fact be very high risk. Although from 1970 through 2009, 32 percent of serial murder cases included victims who were female sex workers, more recently, from 2000 through 2009, the proportion of serial murder cases involving such victims climbed to 69 percent of the total, and serial murderers who kill sex workers continue to kill over longer timespans and amass more victims.⁷¹ Rather than paying less attention to a missing sex worker who is assumed to live a transient lifestyle and perhaps to have outstanding warrants, you should treat the disappearance of sex workers as high-risk cases.

* The Herbert Baumeister (Indianapolis), Robert Berdella (Kansas City, Missouri), Jeffrey Dahmer (Milwaukee, Wisconsin), John Wayne Gacy (Chicago), and Robert Lee Yates (Spokane, Washington) cases all included a significant proportion of “missing missing” victims (Quinet 2009).

Homeless persons

Another group of missing persons not likely to be reported as missing is the homeless, especially those with mental illness. Those who are reported as missing are commonly reported by staff at homeless shelters; many are repeatedly reported as missing, and many are reported when they fail to return to the shelter when they are expected to do so. Most are eventually located alive, having gone missing voluntarily.⁷² This population of missing persons may have become so estranged from family and friends that no missing persons report is filed, and if they are located by police and are older than 21, the police are not allowed to disclose their location to those reporting them as missing, thus creating stress for families and friends and potential frustration with police.

Homeless persons who are reported missing are more likely than other missing persons to be found having died by suicide.⁷³

Undocumented immigrants

Undocumented immigrants are also likely to be part of the “missing missing” population. This population in Arizona constitutes a large part of the unidentified-dead population.⁷⁴ These undocumented border crossers are technically not missing persons in the United States but may have missing persons reports in Mexico, thus requiring cooperation between the U.S. and Mexican governments and police. This issue is increasing in frequency, and a recent symposium on border crossing deaths finds that in a six-year period, as many as 1,000 persons died trying to cross into Arizona.⁷⁵ In Mexico, families can enter information about their missing into a database that can then be checked by missing victims’ advocates in the United States; in the event that unidentified remains are located in a U.S. medical examiner’s office, fingerprints and DNA matching can bring closure for some families.⁷⁶ U.S. Customs and Border Protection has launched a Missing Migrants program to try to reduce deaths among border crossers.⁷⁷

Human trafficking victims

In addition to those voluntarily crossing into the United States, others are brought here against their will. Although the exact number of persons trafficked into the United States is not known, if they escape their traffickers, their disappearance may never be reported to police and, although they are missing persons, their eventual discovery may be through investigation of other criminal activity or of unidentified remains.*

* See Problem-Specific Guide No. 38, Exploitation of Trafficked Women, 2nd Edition, for additional information.

Missing and Murdered Indigenous Persons (MMIP)

The issue of Missing and Murdered Indigenous Persons (MMIP)† overlaps with the categories of missing children and missing adults but merits special consideration for both the seriousness of the problem and its special aspects.⁷⁸ This special category of missing persons cases gets its own classification because of the unique circumstances surrounding tribal sovereign nation status.

† Other common names for this movement are Missing and Murdered Indigenous Women and Girls (MMIWG) and Missing and Murdered Indigenous Relatives (MMIR).

For the purposes of this research, the labels Indigenous peoples, Native Americans, and American Indians (including Alaska Natives) will be used interchangeably. Lisa Monchalin offers a definition we will use: “The term Indigenous is used throughout this paper to refer to original peoples in North America and their descendants.”⁷⁹ This term refers collectively to First Nations, Inuit, and Métis peoples in Canada but has also been used to refer to Indigenous peoples worldwide.⁸⁰

Colonization, assimilation, and unresolved historical trauma

Historical trauma refers to a complex and collective trauma experienced through time and across generations by a group of people who share an identity, affiliation, or circumstance.⁸¹ In context, it refers to the collective, cumulative, and intergenerational traumatic experiences of Native American communities that impact descendants of the initial primary victims.

The effects of unresolved historical trauma resulting from the genocidal policies, both eliminationist and assimilative, used against this population can manifest in numerous ways, including the loss of traditional values or beliefs, substance use, depression, anxiety, suicidal ideation, abuse, post-traumatic stress disorder (PTSD), and violence. Unresolved trauma is a significant contributing factor for Indigenous peoples’ involvement in risky behaviors that lead to unexplained disappearance or death.⁸²

Indigenous victimization

It is estimated that more than four of five American Indian and Alaska Native women have experienced some form of violence in their lifetimes; in some counties, Indigenous women experience violent victimization at a rate 10 times the national average.⁸³ Homicide is a leading cause of death for American Indians / Alaska Natives (AI/AN).⁸⁴ Further, Indigenous men also experience high rates of violence. The CDC estimates that non- Hispanic American Indian / Alaska Native men younger than 55 face the greatest risk of experiencing homicide of all races or ethnicities.⁸⁵

Tribal sovereignty

As of April 2024, there are 574 federally recognized Native American tribes in the United States that possess tribal recognition and sovereignty. Tribal sovereignty refers to the Constitutional rights of Native Americans to self-govern, create tribal law, and establish their own justice systems. Like the U.S. government, tribal nations are vested with authority to manage tribal affairs and maintain welfare and safety of tribal citizens. However, this sovereignty status has been repeatedly challenged since 1831, with the  latest U.S. Supreme Court decision issued in 2021.*

* Cherokee Nation v. Georgia (1831) held that tribal nations had the legal right to self-governance and legally defined the relations between the U.S. government and tribal nations. In 2021, the decision in United States v. Cooley

(https://www.scotusblog.com/case-files/cases/united-states-v-cooley/) held that tribal nations’ police officers can conduct limited investigatory stops of nontribal members on public highways within reservations for violation of state and federal law.

Throughout U.S. history, the U.S. Congress has passed legislation that has vacillated between two conflicting themes in Native American affairs: assimilation policies mandating Native Americans enter the American mainstream vs. policies supporting tribal self-government and self-determination; however, far more legislation has eroded tribal self-governance than supported it. These dramatic swings in public policy have had severe social and psychological effects on many Native Americans (see the earlier section Colonization, assimilation, and unresolved historical trauma).

Federal legislative and policy initiatives

Article I, Section 8 of the Constitution states that “Congress shall have the power to regulate Commerce with foreign nations and among the several states, and with the Indian tribes,” establishing that Indian tribes were separate from the federal government, the states, and foreign nations.⁸⁶ The Indian Appropriations Act of 1871 ended the recognition of independent Native nations and reclassified Native nations as domestic dependent nations subject to applicable federal laws.

In 1877, the General Allotment Act or Dawes Act was passed. This law delegated authority to the Bureau of Indian Affairs (BIA) to allot parcels of tribal land to individual Indians. Under the Dawes Act, large amounts of tribal land not allotted to individual Native Americans was made available for the taking by White people. This created a checkerboard pattern of ownership of traditional tribal lands by tribes, tribal members, and non-Indian homesteaders. Congress then adopted the General Allotment (Severalty) Act of 1887, a policy of removing Native Americans from their ancestral lands, and established the reservation system that exists to this day.

This assimilation policy extended to removing Native American children from their homes and forcing them to attend off-reservation boarding schools. In 1887, to provide funding for more boarding schools, Congress passed the Compulsory Indian Education Act. The American government believed they were rescuing these children from a world of poverty and depression and teaching them life skills. This legislation has arguably had a more devastating impact on the fabric of Native American culture than any other federal policy.

Many Native American children were sent to BIA boarding schools, where they had their hair cut, were prohibited from speaking their native languages, and were punished for traditional Native American cultural practices in the effort to rapidly assimilate them into mainstream White society. “Virtually imprisoned in the schools, children experienced a devastating litany of abuses, from forced assimilation and grueling labor to widespread sexual and physical abuse.”⁸⁷

The Carlisle Indian Industrial School exemplifies these policies. Lieutenant Richard Pratt, a former U.S. Army officer, founded the Carlisle School and is responsible for advocating the off-reservation education of Native Americans to immerse them into the White culture. Pratt is quoted as saying, “A great general has said that the only good Indian is a dead one. In a sense, I agree with the sentiment, but only in this: that all the Indian there is in the race should be dead. Kill the Indian in him, and save the man.”⁸⁸ The Carlisle School was the model for BIA boarding schools across the country, such as the Mount Pleasant Indian Industrial Boarding School in Mt. Pleasant, Michigan and the Industrial Indian Boarding School in Haskell, Kansas. Gloria King, a Saginaw Chippewa, discusses these schools’ effect on her family:

I would like to show you my mama’s picture. This was taken when my mom was about 89 years old. I love my mom. She was a hard worker. Someone asked me one time if my mom, because she had raised three children, was she a good parent? How did her parenting skills affect my parenting skills?

And I laughed. I just laughed out loud. I said, my mother had no parenting skills. She went to an Indigenous boarding school. She went to Mount Pleasant. And when she was quite young, probably 9 or 10, she was put on a train with many other Indigenous children. And they were taken to Haskell, Kansas, to the Industrial Indian Boarding School in Haskell, Kansas. And that’s where she stayed until she was probably 17 or 18 and graduated—I don’t know if that’s the word they used, but until she was finished with her education there. And then she came back to Michigan. But they didn’t teach Indian children how to be parents. They taught them how to be domestics and bakers and farmers and servants.⁸⁹

In 1934, Congress passed the Indian Reorganization Act of 1934 (IRA) into law. This law promoted tribal self-government and encouraged tribes to adopt constitutions and to form chartered corporations. Then, in 1953, House Concurrent Resolution 108 (HCR 108) was adopted, calling for terminating tribal self-government and forcing tribal members to assimilate into White society as rapidly as possible.

These policies and their implementation are entwined with the challenges that Native Americans experience in American society today.

Law enforcement and federal action

Law enforcement jurisdictions on reservations can make it difficult to prosecute some crimes, including sex trafficking. After the 1978 U.S. Supreme Court case Oliphant v. Suquamish Indian Tribe decided that Indian tribal courts have no criminal jurisdiction over non-Indians,⁹⁰ it became illegal for non-Natives to be tried under tribal laws, even if the crime occurred on tribal land. This made it very difficult for real justice to be served to trafficking victims, because sex traffickers tended to overwhelmingly be non-Native, and even when the perpetrators are Native members, the maximum sentence that tribal law can impose is three years. With such little deterrence, non-Native traffickers could easily recruit Native women and girls into the sex trade.⁹¹

The MMIP grassroots movement originated in Canada in the mid-2000s, calling public and government attention to the violence against Indigenous women. This prompted federal U.S. legislation to examine the disproportionate unresolved homicide and missing persons cases involving Indigenous victims, as well as working groups across the nation to create local, state, and national task forces to investigate the scope of this issue. In 2018, the 115th Congress declared May 5 the National Day of Awareness of Missing and Murdered Native Women and Girls. In May 2023, the President addressed a proclamation on MMIP to heighten awareness and urge lawmakers to respond to the crisis.

Public Law No. 116–165, or Savanna’s Act, signed into law in October 2020, was a bipartisan effort to improve the federal response to MMIP, including by increasing coordination among federal, state, tribal, and local law enforcement agencies.⁹² Also signed into law in that month was the Not Invisible Act of 2019, the first bill in history to be introduced and passed by four U.S. congressional members enrolled in their respective federally recognized tribes, led by then-Congresswoman Deb Haaland of New Mexico.⁹³ As Secretary of the Interior, Haaland is now working in coordination with Attorney General Merrick Garland to implement the Not Invisible Act. They have established the Not Invisible Act Commission, a cross-jurisdictional advisory committee composed of law enforcement, tribal leaders, federal partners, service providers, family members of missing and murdered individuals—and, most importantly, survivors. The commission’s purpose is to develop recommendations through the work of six subcommittees focused on improving intergovernmental coordination and establishing best practices for state, tribal, and federal law enforcement to bolster resources for survivors and victims’ families and on combating the epidemic of missing persons and of the murder and trafficking of American Indian and Alaska Native peoples, as specified under the law. The commission’s report is available along with the joint response from the U.S. Departments of the Interior and Justice.⁹⁴

Special risk factors for Native Americans

The available research on risk factors for runaway incidents consistently finds that an individual’s race, ethnicity, and gender can increase their risk of running away, especially alongside other life stressors.⁹⁵ In 2021, NCMEC reported that the most common case type reported to them was endangered runaways, of whom 55 percent were female. With a mean age of 15, Native American endangered runaways were slightly older than endangered runaways of other racial and ethnic backgrounds.⁹⁶ A year earlier, the American Academy of Pediatrics stated in a clinical report that girls of color were at a significantly higher risk of running away than White girls;⁹⁷ among youth who called the National Runaway Safeline, Black, multiracial, and female adolescents were overrepresented compared to the general population.⁹⁸ Running away and homelessness often go hand in hand, with common risk factors such as family dynamics, substance abuse, mental illness, socioeconomic disadvantage, and education present among both adults and juveniles.⁹⁹ Runaway Black girls in particular commonly report family dynamics, childhood abuse, and frequent substance use as reasons for leaving home.¹⁰⁰ While these factors are common among all runaways regardless of gender or race, women and girls of color experience them at disproportionate rates.

Substance use is frequent among runaways, with 67 percent of missing and runaway children reporting having used drugs at least once.¹⁰¹ Among a sample of runaway youth living in shelters, more than half of whom were girls of color, 40 percent were found to have a substance use diagnosis, alcohol and marijuana being the substances most commonly used.¹⁰² The available literature varies in how it ascribes causality: While one study found that runaway risk was predicted by substance use among Black girls in foster care,¹⁰³ new research supports the theory that substance use is a consequence of homelessness, not a cause.¹⁰⁴ Substance use has been shown to be increasingly common among populations of homeless women¹⁰⁵ and often goes hand in hand with mental health problems; Slesnick and Prestopnik reported in their study that more than one-third of their sample of runaway youth were diagnosed with both mental health and substance use disorders.¹⁰⁶ Women and girls who are homeless or runaways report higher rates of mental health issues than men and boys; these rates are even higher for non-White women and girls.¹⁰⁷ Specifically, Black women and girls are more likely to have schizophrenia than women and girls of other ethnicities and more likely to be diagnosed with depression than Black men and boys.¹⁰⁸ Among runaway youth, disengagement from school was a significant risk factor;¹⁰⁹ compared to the general population, homeless young adults were 346 percent more likely to lack a GED or high school diploma.¹¹⁰ Girls of color are especially likely to be affected by this factor, as evidenced by their higher rates of in-school suspensions.¹¹¹ Adolescents who run away are more likely to attend school irregularly, be suspended, or be expelled.¹¹² One common theme among the lives of homeless and runaway women and girls is a history of both physical and sexual abuse, a risk factor that, once again, is highest among girls of color.¹¹³

Adult women often report running from homes because of domestic violence;¹¹⁴ domestic violence is more likely to occur among those experiencing poverty and to Black and Hispanic individuals.¹¹⁵ Before running away or becoming homeless, girls of color often report a history of foster care.¹¹⁶ Research on a sample of 53,610 foster care youth found that Black and Hispanic girls ran away from foster care at significantly higher rates than their White peers.¹¹⁷ Runaway youth and adults experience a variety of risk factors that increase their probability of fleeing; women and girls of color are overexposed to abuse and neglect at school and at home and have a higher probability of being diagnosed with mental health and substance use disorders, fueling their motivation to run away.¹¹⁸

The scope of the MMIP problem itself has had alarming impacts, long recognized by tribal communities alongside the effects of historical trauma. Well before the Federal Government’s belated recognition of the problem in 2018, Indigenous families were demanding justice for the numerous unexplained disappearances and murders of their loved ones. Obstacles to awareness include a limited pool of current data, racial or tribal misclassification in reporting methods, misidentification in existing data, and the overall underreporting of cases involving Indigenous victims in media. All these factors together mean that statistics likely undercount the true extent of the issue, which also hinders creating awareness and support outside of tribal communities.

Jurisdictional complexities

Jurisdiction is complex and creates unique complications for addressing MMIP–related crime on and off tribal lands. As previously mentioned, tribal sovereignty allows tribes to exercise jurisdiction over enrolled tribal members. However, the Federal Government exercises authority over all major crimes that occur on tribal lands.¹¹⁹ In addition, in 1953, P.L. 280 granted five states (six since Alaska statehood in 1959) legal civil and criminal authority over tribal and nontribal citizens on tribal lands within those states.¹²⁰ Then, in 2022, the reauthorization of the Violence Against Women Act expanded tribal authority over nontribal defendants in cases related to stalking, sexual assault, child abuse, and sex trafficking on tribal lands. For MMIP-related cases, determining the primary jurisdiction is based upon numerous factors, such as where the person went missing, whether or not an incident occurred on tribal lands, and level of crime involved. This often puts the burden on Indigenous families and survivors to contact multiple agencies in their attempts to locate their loved one or to file a report.

Geographic challenges

Another distinctive component of MMIP cases is the complications for reporting incidents, responding to incidents, and determining jurisdiction. The majority of tribal lands, often referred to as Indian country,* are rural areas that can have limited cellular, Internet, and other infrastructure, making it difficult for families to call for service or find resources.¹²¹ Socioeconomic barriers can also impact whether families can cover travel costs to file reports at police stations, assist in searches, or receive aid. These geographic challenges also pose difficulties for tribal law enforcement personnel, who provide public safety services for the 5.1 million people who live on reservations.¹²² Of those who reside on reservations, only 1.13 million identify as an American Indian or Alaska Native, but it is the resident’s status that determines whether any of the 3,834 law enforcement officers in the 258 tribal law enforcement agencies can address a crime at hand.¹²³

* Federal law defines Indian country as (a) all land within the limits of any Indian reservation under the jurisdiction of the United States Government, notwithstanding the issuance of any patent, and including rights-of-way running through the reservation; (b) all dependent Indian communities within the borders of the United States whether within the original or subsequently acquired territory thereof, and whether within or without the limits of a state; and (c) all Indian allotments, the Indian titles to which have not been extinguished, including rights-of-way running through the same. (18 USC § 1151 - Indian country defined, June 25, 1948, ch. 645, 62 Stat. 757; May 24, 1949, ch. 139, § 25, 63 Stat. 94.)